The engines installed on many aircraft are housed within a nacelle. Typically, the engine nacelle includes one or more cowl doors that are moveable between open and closed positions. In the open position, the cowl doors allow maintenance personnel to access the interior of the nacelle to repair and maintain the engine.
The movement of the cowl doors between the open and closed positions is accomplished via hydraulic, pneumatic, or electric actuation systems. Hydraulic systems may include one or more hydraulic controllers and hydraulic lines coupled to the aircraft's hydraulic system, and hydraulic actuators connected to the doors. Pneumatic systems may include one or more controllers coupled to one or more pneumatic motors that are coupled to the cowl doors via actuators. Similarly, electric systems may include one or more controllers coupled to one or more electric motors that are coupled to the cowl doors via actuators.
Although presently known hydraulic, pneumatic, and electric cowl door actuation systems are generally satisfactory, each can suffer certain drawbacks. For example, known hydraulic and pneumatic controls can be complex, bulky, and heavy. Whereas known electric systems, while being relatively less bulky and heavy, may allow the cowl doors, due to their own weight, to abruptly impact engine or actuator structure when moving to the closed position.
Hence, there is a need for an improved system and method to control the movement of aircraft engine cowl doors that is safe, simple, reliable, less expensive, light in weight, and will not allow abrupt impact when moving to the closed position. The present invention addresses one or more of these needs.